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界面控件DevExpress WinForms Lookup中文教程 - 如何实现多项目选择?

界面控件DevExpress WinForms Lookup中文教程 - 如何实现多项目选择? 在最新发布的v23.1版本中DevExpress WinForms Lookup Editor查找编辑器引入了一个非常受欢迎的功能——多项选择。在这种新的选择模式下Lookup Editor显示一个带有复选框的列用户可以使用鼠标或键盘选择查找项。DevExpress WinForms拥有180组件和UI库能为Windows Forms平台创建具有影响力的业务解决方案。DevExpress WinForms能完美构建流畅、美观且易于使用的应用程序无论是Office风格的界面还是分析处理大批量的业务数据它都能轻松胜任DevExpress新旧版本帮助文档下载可进QQ qun获取169725316启用多项选择使用EditValueType属性来启用多项选择此属性指定Lookup如何在其EditValue属性中存储所选值。可用的选项包括LookUpEditValueType.ValueList —Lookup将选择的值存储为对象(Listobject)。LookUpEditValueType.CSVString — Lookup将选定的值存储为带有逗号分隔值的字符串。下面的示例演示如何激活多项选择将查找的EditValue属性设置为一个带有id的列表以便在应用程序启动时选择相应的产品。using System.Windows.Forms; using System.Collections.Generic; using System.ComponentModel.DataAnnotations; using DevExpress.XtraEditors; using DevExpress.XtraEditors.Repository; public partial class Form1 : XtraForm { public Form1() { InitializeComponent(); lookUpEdit1.Properties.DataSource ProductA.GetList(); lookUpEdit1.Properties.DisplayMember Name; lookUpEdit1.Properties.ValueMember ID; lookUpEdit1.Properties.EditValueType LookUpEditValueType.ValueList; lookUpEdit1.EditValue new Listobject() {0, 1, 4}; } } public class ProductA { int id; public ProductA(int id) { this.id id; } [Display(Order -1)] public int ID { get { return id; } } [Display(ShortName Bakery Desserts)] public string Name { get; set; } [DisplayFormat(DataFormatString c2)] public double Price { get; set; } public static ListProductA GetList() { return new ListProductA() { new ProductA(0){ Name Butter Cake, Price 56.99 }, new ProductA(1){ Name Chocolate Pie , Price 89.99 }, new ProductA(2){ Name Frozen Cookie Dough, Price 54.99 }, new ProductA(3){ Name Truffie Cake, Price 59.99 }, new ProductA(4){ Name Original Apple Pie, Price 59.99 } }; } }将选定状态绑定到数据Lookup Editor查找编辑器可以保存有关数据源字段中所选项的信息使用CheckBoxSelectorName属性指定包含所选项信息的字段名。如果此字段包含非布尔值类型您还应该处理以下事件来根据需要 convert 字段值QueryCheckBoxSelectorMemberIsSelectedSetCheckBoxSelectorMemberValue如何绑定到布尔数据字段下面的示例演示了如何将选择绑定到“Selected”字段(带有布尔值)public partial class Form1 : XtraForm { public Form1() { InitializeComponent(); lookUpEdit2.Properties.DataSource ProductB.GetList(); lookUpEdit2.Properties.DisplayMember Name; lookUpEdit2.Properties.ValueMember ID; lookUpEdit2.Properties.CheckBoxSelectorMember Selected; lookUpEdit2.Properties.EditValueType LookUpEditValueType.ValueList; lookUpEdit2.EditValue new Listobject() {0, 1}; } } public class ProductB { int id; public ProductB(int id) { this.id id; } [Display(Order -1)] public int ID { get { return id; } } [Display(ShortName Bakery Desserts)] public string Name { get; set; } [DisplayFormat(DataFormatString c2)] public double Price { get; set; } public int InStock { get; set; } [Display(ShortName Add to Order)] public bool Selected { get; set; } public static ListProductB GetProductList() { return new ListProductB() { new ProductB(0){ Name Butter Cake, Price 56.99, InStock 50 }, new ProductB(1){ Name Chocolate Pie , Price 89.99, InStock 32 }, new ProductB(2){ Name Frozen Cookie Dough, Price 54.99, InStock 0 }, new ProductB(3){ Name Truffie Cake, Price 59.99, InStock 42 }, new ProductB(4){ Name Original Apple Pie, Price 59.99, InStock 0} }; } }从下面的截图中可以看到lookup创建了一个选择器列(Add to Order)并将其绑定到“Selected”数据字段。如何绑定到集合属性如果将EditValueType属性设置为LookUpEditValueType.ValueList则可以将查找的EditValue属性绑定到只读集合类型属性这个操作是由EnableEditValueCollectionEditing 设置控制的(默认情况下是启用的)。using System.Windows.Forms; using System.Collections.Generic; using System.ComponentModel.DataAnnotations; using DevExpress.XtraEditors; using DevExpress.XtraEditors.Repository; public partial class Form1 : XtraForm { ListItem orderItems; ListOrder orders; public Form1() { InitializeComponent(); orders new ListOrder(){ new Order(10295), new Order(10296), new Order(10297) }; teOrder.DataBindings.Add(new Binding(EditValue, orders, ID)); dataNavigator1.DataSource orders; orderItems new ListItem() { new Item(){ ID 0, ItemName Butter Cake, Price 56.99 }, new Item(){ ID 1, ItemName Chocolate Pie, Price 89.99}, new Item(){ ID 2, ItemName Frozen Cookie Dough, Price 54.99}, new Item(){ ID 3, ItemName Truffie Cake, Price 59.99 }, new Item(){ ID 4, ItemName Original Apple Pie, Price 59.99 } }; lookupOrderItems.Properties.DataSource orderItems; lookupOrderItems.Properties.DisplayMember ItemName; lookupOrderItems.Properties.ValueMember ID; lookupOrderItems.Properties.EditValueType LookUpEditValueType.ValueList; lookupOrderItems.DataBindings.Add(new Binding(Editvalue, orders, Items)); } } public class Order { int id; public Order(int id) { this.id id; Items new HashSetint(); } [Display(ShortName Order ID)] public int ID { get { return id; } } public HashSetint Items { get; private set; } } public class Item { public int ID { get; set; } public string ItemName { get; set; } public double Price { get; set; } }有条件的选择使用此选项您可以阻止用户根据特定条件选择项目处理SelectionChanging事件并将e.Cancel参数设置为true来取消项目选择。using DevExpress.XtraEditors.Controls; public partial class Form1 : XtraForm { ListProductB products; public Form1() { InitializeComponent(); //... lookUpEdit1.Properties.SelectionChanging Properties_SelectionChanging; } private void Properties_SelectionChanging(object sender, PopupSelectionChangingEventArgs e) { e.Cancel products[e.RecordIndex].InStock 0; } }重要提示WinForms LookUpEdit控件可以选择多个项目GridLookUpEdit、TreeListLookUpEdit和SearchLookUpEdit控件不支持此功能。
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